COMEDK · Physics · 26. Wave Optics
H-polaroid is prepared by
- A stretching polyvinyl alcohol and then heated with dehydrating agent
- B stretching polyvinyl alcohol and then impregnating with iodine
- C orienting herapathite crystal in the same direction in nitrocellulose
- D by using thin tourmaline crystals
Answer & Solution
Correct Answer
(B) stretching polyvinyl alcohol and then impregnating with iodine
Step-by-step Solution
Detailed explanation
H-polaroid is one of the most common type of polaroid used today. It is prepared by stretehing a thin sheet of polyvinyl alcohol and then impregnating it with iodine. In this process, the molecules get oriented in the direction of the applied strain and the material becomes…
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